Electronic Rear Derailleur Positioning System
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing electric rear chain guides experience inaccuracy in speed change due to wear, causing the main drive gear, first gear, and second gear to loosen, leading to failures in transmission between the movable portion, fixing portion, and guiding member.
Innovation Solution
An electronic rear derailleur with a positioning system that includes a main board with a position sensor and a positioning shaft with a magnetic field generation unit, which detects changes in angular position to correct parameters in a controller, restoring normal speed change positioning.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the derailleur uses a mechanical gear transmission system, then it achieves speed change functionality, but the gears become loose due to wear over time, causing transmission inaccuracy
Solution Approach 1:
The patent implements a feedback mechanism using a position sensor to detect the actual position of the movable portion and compare it with the target position. When gear wear causes transmission inaccuracy, the sensor detects the position deviation and sends feedback signals to the control unit, which then adjusts the drive motor to compensate for the error, maintaining accurate chain positioning despite mechanical wear over time.
Solution Approach 2:
The patent replaces the purely mechanical transmission system with an electromechanical system that uses a drive motor, position sensor, and control unit. This substitution allows the system to detect and correct transmission inaccuracies caused by gear wear, transforming a passive mechanical system into an active controlled system that can compensate for mechanical degradation.
2Duration of action of stationary object
If the derailleur components are made loose to accommodate wear, then durability is improved, but transmission precision deteriorates
Solution Approach 1:
The position sensor continuously monitors the actual position of the movable portion and provides feedback to the control unit. When wear causes components to become loose and positioning accuracy to deteriorate, the feedback mechanism detects the deviation and enables the control unit to compensate by adjusting the drive motor, thereby maintaining positioning precision despite component loosening.
Solution Approach 2:
The system performs preliminary correction by detecting position deviations caused by wear and compensating for them before they significantly impact performance. The control unit proactively adjusts the transmission parameters based on sensor feedback, preventing accumulation of positioning errors that would result from component loosening.
3Reliability
If a positioning system with sensor is added, then transmission accuracy is restored after wear, but device complexity increases
Solution Approach 1:
The positioning system uses a position sensor to detect the actual position of the movable portion and provides feedback to the control unit. This feedback mechanism enables the system to detect and correct transmission inaccuracies caused by gear wear, restoring speed change accuracy by dynamically adjusting the transmission parameters based on real-time position information.
Solution Approach 2:
The derailleur system performs self-diagnosis and self-correction through the position sensor and control unit. When wear causes transmission inaccuracy, the system automatically detects the deviation and adjusts itself without external intervention, maintaining accurate speed change functionality. The system serves itself by monitoring and correcting its own performance degradation.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system effectively corrects transmission inaccuracies caused by gear loosening, ensuring precise angular positioning and maintaining normal speed change functionality over time.
Implementation Method 1
a positioning shaft configured to rotate with a first driven gear, the positioning shaft including a magnetic field generation unit in a direction facing the position sensor
Data Source
AI summary
An electronic rear derailleur of the disclosure includes a movable portion including a main drive gear meshing with a first driven gear and a second driven gear, a support frame disposed on the movable portion and for the main drive gear, the first driven gear, and the second driven gear to perform positioning, a drive unit configured to drive, by using a transmission assembly, the main drive gear to rotate, and a positioning system including: a main board, a processing unit and a position sensor disposed on the main board, and a positioning shaft including a magnetic field generation unit facing the position sensor, and receiving, by using the processing unit, positioning information sent by the position sensor. The position sensor is configured to detect a change in an angular position to correct a parameter, thereby restoring a speed change function for normal speed change positioning.